Commit Graph

1432 Commits

Author SHA1 Message Date
Fangrui Song e690137dde [Support] Change compression::zlib::{compress,uncompress} to use uint8_t *
It's more natural to use uint8_t * (std::byte needs C++17 and llvm has
too much uint8_t *) and most callers use uint8_t * instead of char *.
The functions are recently moved into `llvm::compression::zlib::`, so
downstream projects need to make adaption anyway.
2022-07-13 16:26:54 -07:00
Martin Storsjö b069801ffb [clang] [Serialization] Fix swapped PPOpts/ExistingPPOpts parameters. NFC.
The two first parameters of checkPreprocessorOptions are "PPOpts, ExistingPPOpts".
All other callers of the function pass them consistently.

This avoids confusion when working on the code.

Differential Revision: https://reviews.llvm.org/D129277
2022-07-09 00:11:45 +03:00
Cole Kissane ea61750c35 [NFC] Refactor llvm::zlib namespace
* Refactor compression namespaces across the project, making way for a possible
  introduction of alternatives to zlib compression.
  Changes are as follows:
  * Relocate the `llvm::zlib` namespace to `llvm::compression::zlib`.

Reviewed By: MaskRay, leonardchan, phosek

Differential Revision: https://reviews.llvm.org/D128953
2022-07-08 11:19:07 -07:00
Volodymyr Sapsai 2ceb9c347f [ODRHash diagnostics] Move common code for calculating diag locations in `DiagnoseODRMismatch` into a lambda. NFC.
Differential Revision: https://reviews.llvm.org/D128489
2022-06-30 19:39:22 -07:00
Volodymyr Sapsai 15cb180dcb [ODRHash diagnostics] Split `err_module_odr_violation_mismatch_decl_diff` into per-entity diagnostics. NFC.
We'll need to add more cases for Objective-C entities and adding
everything to `err_module_odr_violation_mismatch_decl_diff` makes it
harder to work with over time.

Differential Revision: https://reviews.llvm.org/D128488
2022-06-30 18:40:46 -07:00
Volodymyr Sapsai 3514131219 [ODRHash diagnostics] Fix typos. NFC. 2022-06-29 14:59:37 -07:00
Volodymyr Sapsai 017c068f78 [ODRHash diagnostics] Move repetetive code at lambda calls into lambdas themselves. NFC.
It helps to avoid copy-paste mistakes and makes custom code paths more
noticeable.

Not funnelling all diagnostic through `ODRDiagDeclError` because plan to
break down `err_module_odr_violation_mismatch_decl_diff` into smaller
pieces instead of making it bigger and bigger.

Differential Revision: https://reviews.llvm.org/D128487
2022-06-29 13:24:55 -07:00
Kazu Hirata 06decd0b41 [clang] Use value_or instead of getValueOr (NFC) 2022-06-18 23:21:34 -07:00
Matthias Gehre 7e17e15c9f clang: Introduce -fexperimental-max-bitint-width
This splits of the introduction of -fexperimental-max-bitint-width
from https://reviews.llvm.org/D122234
because that PR is still blocked on discussions on the backend side.

I was asked [0] to upstream at least the flag.

[0] 09854f2af3 (commitcomment-75116619)

Differential Revision: https://reviews.llvm.org/D127287
2022-06-09 07:15:03 +01:00
Aaron Ballman 69da3b6aea Revert "[OpenMP] atomic compare fail : Parser & AST support"
This reverts commit 232bf8189e.

It broke the sanitize buildbot: https://lab.llvm.org/buildbot/#/builders/5/builds/24074

It also reproduces on Windows debug builds as a crash.
2022-05-25 13:34:34 -04:00
Sunil Kuravinakop 232bf8189e [OpenMP] atomic compare fail : Parser & AST support
This is a support for " #pragma omp atomic compare fail ". It has Parser & AST support for now.

Reviewed By: tianshilei1992

Differential Revision: https://reviews.llvm.org/D123235
2022-05-24 23:56:42 -05:00
Mike Rice 9ba937112f [OpenMP] Add parsing/sema support for omp_all_memory reserved locator
Adds support for the reserved locator 'omp_all_memory' for use
in depend clauses with 'out' or 'inout' dependence-types.

Differential Revision: https://reviews.llvm.org/D125828
2022-05-24 10:28:59 -07:00
Sam McCall 1dfd8e99f9 [Serialization] Delta encode locations in expansion sloc entries
This is a 1.9% reduction in PCH size in my measurements.

In abbreviated records, VBR6 seems to be slightl better than VBR8 for locations
that may be delta-encoded (i.e. not the first)

Differential Revision: https://reviews.llvm.org/D125952
2022-05-20 01:05:53 +02:00
Sam McCall 4df795bff7 [Serialization] Delta-encode consecutive SourceLocations in TypeLoc
Much of the size of PCH/PCM files comes from stored SourceLocations.
These are encoded using (almost) their raw value, VBR-encoded. Absolute
SourceLocations can be relatively large numbers, so this commonly takes
20-30 bits per location.

We can reduce this by exploiting redundancy: many "nearby" SourceLocations are
stored differing only slightly and can be delta-encoded.
Randam-access loading of AST nodes constrains how long these sequences
can be, but we can do it at least within a node that always gets
deserialized as an atomic unit.

TypeLoc is implemented in this patch as it's a relatively small change
that shows most of the API.
This saves ~3.5% of PCH size, I have local changes applying this technique
further that save another 3%, I think it's possible to get to 10% total.

Differential Revision: https://reviews.llvm.org/D125403
2022-05-19 09:40:44 +02:00
Richard Howell ee51e9795a [clang] serialize ORIGINAL_PCH_DIR relative to BaseDirectory
This diff changes the serialization of the `ORIGINAL_PCH_DIR`
entry in module files to be serialized relative to the module's
`BaseDirectory`. This will allow for the module to be relocatable
across machines.

The path is restored relative to the module's BaseDirectory on
deserialization.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D124946
2022-05-12 07:31:19 -07:00
Richard Howell f11056943e [clang] serialize SUBMODULE_TOPHEADER relative to BaseDirectory
This diff changes the serialization of the `SUBMODULE_TOPHEADER`
entry in module files to be serialized relative to the module's
`BaseDirectory`. This matches the behavior of the
`SUBMODULE_HEADER` entry and will allow for the module to be
relocatable across machines.

The path is restored relative to the module's `BaseDirectory` on
deserialization.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D124938
2022-05-12 07:29:37 -07:00
Volodymyr Sapsai d32c685e10 [modules] Merge equivalent extensions and diagnose ivar redeclarations for extensions loaded from different modules.
Emitting metadata for the same ivar multiple times can lead to
miscompilations. Objective-C runtime adds offsets to calculate ivar
position in memory and presence of duplicate offsets causes wrong final
position thus overwriting unrelated memory.

Such a situation is impossible with modules disabled as clang diagnoses
ivar redeclarations during sema checks after parsing
(`Sema::ActOnFields`). Fix the case with modules enabled by checking
during deserialization if ivar is already declared. We also support
a use case where the same category ends up in multiple modules. We
don't want to treat this case as ivar redeclaration and instead merge
corresponding ivars.

rdar://83468070

Differential Revision: https://reviews.llvm.org/D121177
2022-04-27 15:52:59 -07:00
Sam McCall e80ee1829c Reland [Frontend] avoid copy of PCH data when PrecompiledPreamble stores it in memory
This reverts commit eadf352707.

The reland fixes a couple of places in clang that were unneccesarily
requesting a null-terminated buffer of the PCH, and hitting assertions.
2022-04-21 21:15:39 +02:00
Jan Svoboda d79ad2f1db [clang][lex] NFCI: Use FileEntryRef in PPCallbacks::InclusionDirective()
This patch changes type of the `File` parameter in `PPCallbacks::InclusionDirective()` from `const FileEntry *` to `Optional<FileEntryRef>`.

With the API change in place, this patch then removes some uses of the deprecated `FileEntry::getName()` (e.g. in `DependencyGraph.cpp` and `ModuleDependencyCollector.cpp`).

Reviewed By: dexonsmith, bnbarham

Differential Revision: https://reviews.llvm.org/D123574
2022-04-14 10:46:12 +02:00
Jennifer Yu 187ccc66fa [clang][OpenMP5.1] Initial parsing/sema for has_device_addr
Added basic parsing/sema/ support for the 'has_device_addr' clause.

Differential Revision: https://reviews.llvm.org/D123402
2022-04-08 21:19:38 -07:00
David Goldman d9739f29cd Serialize PragmaAssumeNonNullLoc to support preambles
Previously, if a `#pragma clang assume_nonnull begin` was at the
end of a premable with a `#pragma clang assume_nonnull end` at the
end of the main file, clang would diagnose an unterminated begin in
the preamble and an unbalanced end in the main file.

With this change, those errors no longer occur and the case above is
now properly handled. I've added a corresponding test to clangd,
which makes use of preambles, in order to verify this works as
expected.

Differential Revision: https://reviews.llvm.org/D122179
2022-03-31 11:08:01 -04:00
Hubert Tong ce21c926f8 [Clang] Work with multiple pragmas weak before definition
Update `WeakUndeclaredIdentifiers` to hold a collection of weak
aliases per identifier instead of only one.

This also allows the "used" state to be removed from `WeakInfo`
because it is really only there as an alternative to removing
processed map entries, and we can represent that using an empty set
now. The serialization code is updated for the removal of the field.
Additionally, a PCH test is added for the new functionality.

The records are grouped by the "target" identifier, which was already
being used as a key for lookup purposes. We also store only one record
per alias name; combined, this means that diagnostics are grouped by
the "target" and limited to one per alias (which should be acceptable).

Fixes PR28611.
Fixes llvm/llvm-project#28985.

Reviewed By: aaron.ballman, cebowleratibm

Differential Revision: https://reviews.llvm.org/D121927

Co-authored-by: Rachel Craik <rcraik@ca.ibm.com>
Co-authored-by: Jamie Schmeiser <schmeise@ca.ibm.com>
2022-03-24 20:17:49 -04:00
Benjamin Kramer 5d2ce7663b Use llvm::append_range instead of push_back loops where applicable. NFCI. 2022-03-18 01:25:34 +01:00
Yonghong Song 3251ba2d0f [Attr] Fix a btf_type_tag AST generation
Current ASTContext.getAttributedType() takes attribute kind,
ModifiedType and EquivType as the hash to decide whether an AST node
has been generated or note. But this is not enough for btf_type_tag
as the attribute might have the same ModifiedType and EquivType, but
still have different string associated with attribute.

For example, for a data structure like below,
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag2"))) __attribute__((btf_type_tag("tag4"))) *b;
  };
The current ASTContext.getAttributedType() will produce
an AST similar to below:
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *b;
  };
and this is incorrect.

It is very difficult to use the current AttributedType as it is hard to
get the tag information. To fix the problem, this patch introduced
BTFTagAttributedType which is similar to AttributedType
in many ways but with an additional BTFTypeTagAttr. The tag itself can
be retrieved with BTFTypeTagAttr.
With the new BTFTagAttributed type, the debuginfo code can be greatly
simplified compared to previous TypeLoc based approach.

Differential Revision: https://reviews.llvm.org/D120296
2022-03-16 08:46:52 -07:00
Alex Lorenz 00cd6c0420 [Preprocessor] Reduce the memory overhead of `#define` directives (Recommit)
Recently we observed high memory pressure caused by clang during some parallel builds.
We discovered that we have several projects that have a large number of #define directives
in their TUs (on the order of millions), which caused huge memory consumption in clang due
to a lot of allocations for MacroInfo. We would like to reduce the memory overhead of
clang for a single #define to reduce the memory overhead for these files, to allow us to
reduce the memory pressure on the system during highly parallel builds. This change achieves
that by removing the SmallVector in MacroInfo and instead storing the tokens in an array
allocated using the bump pointer allocator, after all tokens are lexed.

The added unit test with 1000000 #define directives illustrates the problem. Prior to this
change, on arm64 macOS, clang's PP bump pointer allocator allocated 272007616 bytes, and
used roughly 272 bytes per #define. After this change, clang's PP bump pointer allocator
allocates 120002016 bytes, and uses only roughly 120 bytes per #define.

For an example test file that we have internally with 7.8 million #define directives, this
change produces the following improvement on arm64 macOS: Persistent allocation footprint for
this test case file as it's being compiled to LLVM IR went down 22% from 5.28 GB to 4.07 GB
and the total allocations went down 14% from 8.26 GB to 7.05 GB. Furthermore, this change
reduced the total number of allocations made by the system for this clang invocation from
1454853 to 133663, an order of magnitude improvement.

The recommit fixes the LLDB build failure.

Differential Revision: https://reviews.llvm.org/D117348
2022-02-14 09:27:44 -08:00
Alex Lorenz 3f05192c4c Revert "[Preprocessor] Reduce the memory overhead of `#define` directives"
This reverts commit 0d9b91524e.

This change broke LLDB's build. I will need to recommit after fixing LLDB.
2022-02-11 15:53:16 -08:00
Alex Lorenz 0d9b91524e [Preprocessor] Reduce the memory overhead of `#define` directives
Recently we observed high memory pressure caused by clang during some parallel builds.
We discovered that we have several projects that have a large number of #define directives
in their TUs (on the order of millions), which caused huge memory consumption in clang due
to a lot of allocations for MacroInfo. We would like to reduce the memory overhead of
clang for a single #define to reduce the memory overhead for these files, to allow us to
reduce the memory pressure on the system during highly parallel builds. This change achieves
that by removing the SmallVector in MacroInfo and instead storing the tokens in an array
allocated using the bump pointer allocator, after all tokens are lexed.

The added unit test with 1000000 #define directives illustrates the problem. Prior to this
change, on arm64 macOS, clang's PP bump pointer allocator allocated 272007616 bytes, and
used roughly 272 bytes per #define. After this change, clang's PP bump pointer allocator
allocates 120002016 bytes, and uses only roughly 120 bytes per #define.

For an example test file that we have internally with 7.8 million #define directives, this
change produces the following improvement on arm64 macOS: Persistent allocation footprint for
this test case file as it's being compiled to LLVM IR went down 22% from 5.28 GB to 4.07 GB
and the total allocations went down 14% from 8.26 GB to 7.05 GB. Furthermore, this change
reduced the total number of allocations made by the system for this clang invocation from
1454853 to 133663, an order of magnitude improvement.

Differential Revision: https://reviews.llvm.org/D117348
2022-02-11 15:01:10 -08:00
Chuanqi Xu 8c930cef0e [NFC] [Modules] Refactor ODR checking for default template argument in
ASTReader

This is a cleanup to reduce the lines of code to handle default template
argument in ASTReader.

Reviewed By: urnathan

Differential Revision: https://reviews.llvm.org/D118437
2022-02-10 10:10:10 +08:00
Jan Svoboda f720272330 [clang][lex] Include tracking: simplify and move to preprocessor
This patch replaces the exact include count of each file in `HeaderFileInfo` with a set of included files in `Preprocessor`.

The number of includes isn't a property of a header file but rather a preprocessor state. The exact number of includes is not used anywhere except statistic tracking.

Reviewed By: vsapsai

Differential Revision: https://reviews.llvm.org/D114095
2022-01-26 15:56:26 +01:00
Haojian Wu ab3f100bec Reland (2) "[AST] Add RParen loc for decltype AutoTypeloc.""
The patch was reverted because it caused a crash during PCH build -- we
missed to update the RParenLoc in TreeTransform<Derived>::TransformAutoType.

This relands 55d96ac and 37ec65e with a test and fix.
2022-01-17 11:33:11 +01:00
Florian Hahn eadb4cfeef
Revert (2) "[AST] Add RParen loc for decltype AutoTypeloc."
This reverts commit 41fbdfa4d5.

The commit breaks stage 2 builds with debug info, e.g.
https://green.lab.llvm.org/green/job/clang-stage2-Rthinlto/5088/console

Clang crashes with the following assertion when building
llvm-project/llvm/lib/Support/Timer.cpp

/usr/local/bin/sccache /Users/buildslave/jenkins/workspace/clang-stage2-Rthinlto/host-compiler/bin/clang++  -DGTEST_HAS_RTTI=0 -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Ilib/Support -I/Users/buildslave/jenkins/workspace/clang-stage2-Rthinlto/llvm-project/llvm/lib/Support -Iinclude -I/Users/buildslave/jenkins/workspace/clang-stage2-Rthinlto/llvm-project/llvm/include -fno-stack-protector -fno-common -Wno-profile-instr-unprofiled -fPIC -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -fmodules -fmodules-cache-path=/Users/buildslave/jenkins/workspace/clang-stage2-Rthinlto/clang-build/Build/module.cache -fcxx-modules -Xclang -fmodules-local-submodule-visibility -gmodules -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -fdiagnostics-color -flto=thin  -O2 -g -DNDEBUG -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk   -std=c++14  -fno-exceptions -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/Timer.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/Timer.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/Timer.cpp.o -c /Users/buildslave/jenkins/workspace/clang-stage2-Rthinlto/llvm-project/llvm/lib/Support/Timer.cpp
Assertion failed: (((getOffset()+Offset) & MacroIDBit) == 0 && "offset overflow"), function getLocWithOffset, file /Users/buildslave/jenkins/workspace/clang-stage1-RA/llvm-project/clang/include/clang/Basic/SourceLocation.h, line 135.
2022-01-12 10:09:37 +00:00
Haojian Wu 41fbdfa4d5 Reland "[AST] Add RParen loc for decltype AutoTypeloc."
Reland 55d96ac and 37ec65e with a clang-tidy fix.
2022-01-11 12:06:18 +01:00
Haojian Wu c2293bc17d Revert "[AST] Add RParen loc for decltype AutoTypeloc."
This breaks a clang-tidy check, needs to investigate and fix. Revert
them to bring the buildbot back.

This reverts commit 55d96ac3dc and
37ec65e1d7
2022-01-10 15:18:41 +01:00
Haojian Wu 55d96ac3dc [AST] Add RParen loc for decltype AutoTypeloc.
Differential Revision: https://reviews.llvm.org/D116919
2022-01-10 12:46:27 +01:00
Haojian Wu 4a4b8e4f99 [AST] Add more source information for DecltypeTypeLoc.
Adds the paren source location, and removes the hack in clangd.

Differential Revision: https://reviews.llvm.org/D116793
2022-01-10 09:34:18 +01:00
Kazu Hirata 40446663c7 [clang] Use true/false instead of 1/0 (NFC)
Identified with modernize-use-bool-literals.
2022-01-09 00:19:47 -08:00
Kazu Hirata 6c335b1a45 [clang] Remove unused "using" (NFC)
Identified by misc-unused-using-decls.
2021-12-27 20:48:21 -08:00
Shilei Tian c7a589a2c4 [Clang][OpenMP] Add the support for atomic compare in parser
This patch adds the support for `atomic compare` in parser. The support
in Sema and CodeGen will come soon. For now, it simply eimits an error when it
is encountered.

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D115561
2021-12-24 08:16:51 -05:00
Sam McCall af27466c50 Reland "[AST] Add UsingType: a sugar type for types found via UsingDecl"
This reverts commit cc56c66f27.
Fixed a bad assertion, the target of a UsingShadowDecl must not have
*local* qualifiers, but it can be a typedef whose underlying type is qualified.
2021-12-20 18:03:15 +01:00
Sam McCall cc56c66f27 Revert "[AST] Add UsingType: a sugar type for types found via UsingDecl"
This reverts commit e1600db19d.

Breaks sanitizer tests, at least on windows:
https://lab.llvm.org/buildbot/#/builders/127/builds/21592/steps/4/logs/stdio
2021-12-20 17:53:56 +01:00
Sam McCall e1600db19d [AST] Add UsingType: a sugar type for types found via UsingDecl
Currently there's no way to find the UsingDecl that a typeloc found its
underlying type through. Compare to DeclRefExpr::getFoundDecl().

Design decisions:
- a sugar type, as there are many contexts this type of use may appear in
- UsingType is a leaf like TypedefType, the underlying type has no TypeLoc
- not unified with UnresolvedUsingType: a single name is appealing,
  but being sometimes-sugar is often fiddly.
- not unified with TypedefType: the UsingShadowDecl is not a TypedefNameDecl or
  even a TypeDecl, and users think of these differently.
- does not cover other rarer aliases like objc @compatibility_alias,
  in order to be have a concrete API that's easy to understand.
- implicitly desugared by the hasDeclaration ASTMatcher, to avoid
  breaking existing patterns and following the precedent of ElaboratedType.

Scope:
- This does not cover types associated with template names introduced by
  using declarations. A future patch should introduce a sugar TemplateName
  variant for this. (CTAD deduced types fall under this)
- There are enough AST matchers to fix the in-tree clang-tidy tests and
  probably any other matchers, though more may be useful later.

Caveats:
- This changes a fairly common pattern in the AST people may depend on matching.
  Previously, typeLoc(loc(recordType())) matched whether a struct was
  referred to by its original scope or introduced via using-decl.
  Now, the using-decl case is not matched, and needs a separate matcher.
  This is similar to the case of typedefs but nevertheless both adds
  complexity and breaks existing code.

Differential Revision: https://reviews.llvm.org/D114251
2021-12-20 17:15:38 +01:00
Aaron Ballman 6c75ab5f66 Introduce _BitInt, deprecate _ExtInt
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:

* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.

I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
2021-12-06 12:52:01 -05:00
David Pagan b0de656bdf Initial parsing/sema for 'align' clause
Added basic parsing/sema/serialization support for 'align' clause for use with
'allocate' directive.
2021-11-09 07:34:18 -05:00
Mike Rice 4eac7bcf1a [OpenMP] Add parsing/sema/serialization for 'bind' clause.
Differential Revision: https://reviews.llvm.org/D113154
2021-11-04 14:40:30 -07:00
Volodymyr Sapsai 0a35cc40b8 [clang][objc] Speed up populating the global method pool from modules.
For each selector encountered in the source code, we need to load
selectors from the imported modules and check that we are calling a
selector with compatible types.

At the moment, for each module we are storing methods declared in the
headers belonging to this module and methods from the transitive closure
of imported modules. When a module is imported by a few other modules,
methods from the shared module are duplicated in each importer. As the
result, we can end up with lots of identical methods that we try to add
to the global method pool. Doing this duplicate work is useless and
relatively expensive.

Avoid processing duplicate methods by storing in each module only its
own methods and not storing methods from dependencies. Collect methods
from dependencies by walking the graph of module dependencies.

The issue was discovered and reported by Richard Howell. He has done the
hard work for this fix as he has investigated and provided a detailed
explanation of the performance problem.

Differential Revision: https://reviews.llvm.org/D110123
2021-11-03 17:11:14 -07:00
Kazu Hirata 16ceb44e62 [clang] Use llvm::{count,count_if,find_if,all_of,none_of} (NFC) 2021-10-25 09:14:45 -07:00
Kazu Hirata e567f37dab [clang] Use llvm::is_contained (NFC) 2021-10-13 20:41:55 -07:00
Jan Svoboda 28fa77feeb [clang][modules] Avoid using uninitialized SourceLocation
At this point, `F.ImportLoc` has not been initialized by the `ASTReader` yet and using it leads to an assertion failure.

Introduced in 638c673a8c and 4445135109.
2021-10-13 11:24:01 +02:00
Jan Svoboda 6a1f50b84a [clang][deps] Prune unused header search paths
To reduce the number of explicit builds of a single module, we can try to squash multiple occurrences of the module with different command-lines (and context hashes) by removing benign command-line options. The greatest contributors to benign differences between command-lines are the header search paths.

In this patch, the lookup cache in `HeaderSearch` is used to identify paths that were actually used when implicitly building the module during scanning. This information is serialized into the unhashed control block of the implicitly-built PCM. The dependency scanner then loads this and may use it to prune the header search paths before computing the context hash of the module and generating the command-line.

We could also prune the header search paths when serializing `HeaderSearchOptions` into the PCM. That way, we could do it only once instead of every load of the PCM file by dependency scanner. However, that would result in a PCM file whose contents don't produce the same context hash as the original build, which is probably highly surprising.

There is an alternative approach to storing extra information into the PCM: wire up preprocessor callbacks to capture the used header search paths on-the-fly during preprocessing of modularized headers (similar to what we currently do for the main source file and textual headers). Right now, that's not compatible with the fact that we do an actual implicit build producing PCM files during dependency scanning. The second run of dependency scanner loads the PCM from the first run, skipping the preprocessing altogether, which would result in different results between runs. We can revisit this approach when we stop building implicitly during dependency scanning.

Depends on D102923.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D102488
2021-10-12 12:39:23 +02:00
Jan Svoboda 638c673a8c [clang][modules] NFC: Propagate import `SourceLocation` into `HeaderSearch::lookupModule`
This patch propagates the import `SourceLocation` into `HeaderSearch::lookupModule`. This enables remarks on search path usage (implemented in D102923) to point to the source code that initiated header search.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D111557
2021-10-12 09:31:51 +02:00